the converter refuses to work due to error

I am trying to convert https://github.com/blue-mood/blue-mood-kate to a kate color theme. the converter gives me a vague error that I do not know what to do with. this is the error

$ python3 kateschema_to_theme_converter.py bluemood Blue\ Mood.kateschema 
Traceback (most recent call last):
  File "/home/me/syntax-highlighting/utils/kateschema_to_theme_converter.py", line 281, in <module>
    main(str(sys.argv[2]))
  File "/home/me/syntax-highlighting/utils/kateschema_to_theme_converter.py", line 266, in main
    jsonConfig["custom-styles"] = extractCustomStyles(config)
  File "/home/me/syntax-highlighting/utils/kateschema_to_theme_converter.py", line 248, in extractCustomStyles
    extractCustomStyle(config[value], realKey)
  File "/home/me/syntax-highlighting/utils/kateschema_to_theme_converter.py", line 223, in extractCustomStyle
    style = decodeTextStyle(value)
  File "/home/me/syntax-highlighting/utils/kateschema_to_theme_converter.py", line 159, in decodeTextStyle
    style = jsonConfig["text-styles"][indexToStyle[styleIndex]].copy()
KeyError: 'Error'